ZyXEL Communications P-873HNU-51B, User Manual

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Chapter 10 Quality of Service (QoS)
P-873HNU(P)-51B User’s Guide
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The following table describes the labels in this screen.
10.8 Technical Reference
The following section contains additional technical information about the VDSL Router features
described in this chapter.
IEEE 802.1Q Tag
The IEEE 802.1Q standard defines an explicit VLAN tag in the MAC header to identify the VLAN
membership of a frame across bridges. A VLAN tag includes the 12-bit VLAN ID and 3-bit user
priority. The VLAN ID associates a frame with a specific VLAN and provides the information that
devices need to process the frame across the network.
IEEE 802.1p specifies the user priority field and defines up to eight separate traffic types. The
following table describes the traffic types defined in the IEEE 802.1d standard (which incorporates
the 802.1p).
Table 40
Network Settings > QoS > Monitor
LABEL DESCRIPTION
Refresh Interval Enter how often you want the VDSL Router to update this screen. Select None
to stop refreshing statistics.
Interface Monitor
# This is the index number of the entry.
Name This shows the name of the interface on the VDSL Router.
Pass Rate This shows how many packets forwarded to this interface are transmitted
successfully.
Drop Rate This shows how many packets forwarded to this interface are dropped.
Queue Monitor
# This is the index number of the entry.
Name This shows the name of the queue.
Pass Rate This shows how many packets assigned to this queue are transmitted
successfully.
Drop Rate This shows how many packets assigned to this queue are dropped.
Table 41
IEEE 802.1p Priority Level and Traffic Type
PRIORITY
LEVEL
TRAFFIC TYPE
Level 7 Typically used for network control traffic such as router configuration messages.
Level 6 Typically used for voice traffic that is especially sensitive to jitter (jitter is the
variations in delay).
Level 5 Typically used for video that consumes high bandwidth and is sensitive to jitter.
Level 4 Typically used for controlled load, latency-sensitive traffic such as SNA (Systems
Network Architecture) transactions.
Level 3 Typically used for “excellent effort” or better than best effort and would include
important business traffic that can tolerate some delay.
Level 2 This is for “spare bandwidth”.